Preheat oven to 350 degrees Fahrenheit and grease a loaf pan with butter or non-stick spray. Whisk together the egg, pumpkin, applesauce, and water. In a separate bowl, mix together the rest of the ingredients, except for the walnuts. When mixed, combine dry and wet mixture, and add in chopped walnuts. Pour into loaf pan and garnish the top of the loaf with walnut halves. Bake for 45-50 minutes, or until a toothpick comes out clean.